Trust is often thought to be one of the most crucial building blocks to any relationship. But some lies may be good for society.

In simulations, small fibs — such as lying to avoid hurting someone’s feelings — appeared to help to build communities and form connections among individuals in a social network. Larger lies — such as lying about stealing or cheating — can fragment those networks, making it harder for them to grow. The lies, whether big or small, can shape social networks and ultimately society as a whole, researchers argue July 23 in the Proceedings of the Royal Society B.